Valve seat grinding tool



Sept. 23, 1952 v|| M, EMGE VALVE SEAT GRINDING TooL 2 SHEETSP-SHEET l Filed May 1, 1951 ffl? INVENToR. #6255er M. E4/16E .BY man //zr Sept. 23, 1952 H, M, EMGE vALvEsEAT GRINDING TooL 2 SHEETS-SHEET 2 Filed May 1, 1951 mglimmmm,

,Zelf/@fa INVENTOR. HERBERTM EMGE both the inner race of bearing |6 and the upper end of the inner` sleeve. A centered hexagonal socket 3| provided in plug 28 serves for the application of a portable motor driven wrench or other high speed stone rotating means. Thus the assembly is held together by the threaded plug or bushing 28-maintaining the .bearings l5, I6 and hence the inner sleeve 3, in position.

The axial bore 32 of the inner sleeve is dimensioned for a close sliding fit about the removable -pilot stem P. To prevent rotation of the inner 'sleeve about the pilot stem during the grinding loperz'altions, and hence to avoid wear therebetween, steel balls 33, movable in the radial pockets or holes 34 of the -inner sleeve and projecting into longitudinal grooves 35 of the stem,lprovide rotational purchase between the inner sleeve and the f pilot stem P'. A taper or an inner retaining lip 31 at the inner part of the holes 34 and a ball're- `taining band or sleeve A36`prevent the` balls from slipping out of the pockets. A slight rotation of the stone sleeve upon insertion of the pilot stem 'brings' 'theballs' into coincidence Vwith the 'longi- 4tudinal,groovesjto allow the'pilot to slide into the 'inner sleeve. Thereafter'further rotation of the vinner sleeve with respect to the pilot stern is prevented, though the inner sleeve is slidablefreely on thejpilot.

' Inv the upper end of the inner sleeve there is provided a thimble-like plunger 40 urged'downnwardly by sleeve lifting spring 4| toward a limiting position determined by the shoulder 42 serving as 'astop for the flange 43 on the upper end ofthe plunger. Hence, neither the plunger lnor the'lifting V springcan escape from the stonesleeve assembly `when it is removed from the pilot stem.. The upper end of the springV 4| is held fin centeredposition by the'spring locatingdisk k44 vwhich isretainedV in the sleeve V| 3 bythe snap ring 45 engaginga groove cut in the inner surface ofthe inner sleeve end. 'Thus when the stone sleeve is on the pilot stem,` as long as no Adownward pressure is applied to the st one sleeve, theplunger 40 in contact with the upper-end of thef pilot stem holds the stone lifted outofcontaetjvithlthe valveseat, as shownrinFig. 1, where -thedriving. spindle of the power tool is represented injoutline form out of driving engagement Awith socket 3|. 'When a power vwrench'or4 other 'driving means is applied to the sleeve,` (Fig. 3) I the vdownward pressureA thereof depresses the stone sleeve against the bias of the spring 4| as the' plunger 4|),k is moved upwardly by Athe pilot 'sternjP relative to the sleeve.,thus allowing the `Stonve'tocome to working contact withv the seat to be ground. Assoon as the grinding pressure is released or the driving tool is removed from thesocket 3|, the-sleeve is immediately 'raised by the action of the spring to lift the stone out of contact with the surface. Hence, inarring of thel finished valve seat, caused by the stone dragging thereon during rotation after driving pressure isjremoved, is prevented. The length of the longitudinal grooves35,v of the plunger 40 and of the space between disk 44 and shoulder 42 are, of course, dimensioned toY accommodate a variety of' actual-pilot stern lengthsor effective lengths resulting` from different .clamping adjustments and use in valve stemA guides of varying lengths. Y This invention may be embodied in other forms than that shown specifically in the drawings and described in the foregoing specification, -and hence the scope of the invention is indicated by the following claims rather than vthe foregoing through said tubular extension,

illustrative description. All changes coming within the meaning and range of equivalency of the claims are, therefore, intended to be embraced therein.

I claim:

l. A valve seat grinding stone sleeve adapted for use on a pilot stem clamped coaxially in a valve stem bore comprising a rotatable hollow cylinder provided at its upper end with means for a driving engagement by a separate power driving means and at its lower end with a coaxial tubular extension for mounting a valve seat grinding stone thereon. an inner sleeve to receive the upper end of a pilot stem inserted anti-friction bearing means rotatably mounting said hollow cylinder to said inner sleeve, a plunger movable in the upper end of the bore of said inner sleeve to engage the top of a pilot stem, the upper end of `said inner sleeve being counterbored to provide an internal shoulder in the bore thereof and the plunger being provided with a retaining rim to engage said shoulder, bore closure means within said counterbore including a disc and a snap ring outward of said disc and engaged in a snap ring groove in said counterbore, and a compression spring interposed between said closure and said plunger biasing said plunger toward said shoulder, whereby the stone sleeve may be depressed relative to the pilot stem and will be lifted relative to the stem upon release of the depressing force. y

l l2. A valve seat grinding mechanism comprising a'pilot stem clampable coaxially in a valve stem bore and a rotary grinding stone carrier, said carrier comprising a rotatable hollow cylinder provided with means for a driving engagement bya separate power driving means and at its lower end with a coaxial tubular extension for mounting a valve seat grinding stone thereon, an innersleeve to receive the upper end of said pilot stem inserted through said tubular extension, anti-friction bearing means rotatably mounting said hollow cylinder tov said inner sleeve, pilot stem engaging means carried by the inner sleeve adapted'to prevent rotation of said inner sleeve on the pilot stem, a plunger movable in the upper end of the bore of said inner sleeve to engage the top of said pilot stem, the upper end of said inner sleeve being counterbored to provide an internal shoulder in the bore thereof and the plunger being provided with a retaining rim to engage said shoulder, bore closure means within said counterbore including a disc and a snap' ring outward of said disc and engaged in a snap ring groove in said counterbore, and a compression spring interposed between said closure and said plunger biasing said plunger toward said shoulder, whereby the stone sleeve may-bedepressed relative to the pilot stem and will be lifted relative to the stem upon release ofthe depressing force. I

3.A Al valve seat grinding stone sleeve adapted for use on a pilotV stem clamped coaxially in a valve stern bore comprising a rotatable hollow cylinder provided atv its upper end with means for driving engagement by a separate power driving means and at its lower end with a coaxial tubular extension for mounting a valve seat grinding stone thereon.- an inner sleeve to receive the vupper end of a pilot stem inserted throughsaid tubular extension, anti-friction bearing meansrotatably mounting said hollow cylinder to said inner sleeve, a plunger movable in the upper part of the bore of said inner sleeve to engage the top of a pilot stem, the upper end of said inner sleeve being counterbored to provide an'internal shoulder in the bore thereof and the plunger being provided with a retaining rim to engage said shoulder, bore closure means within said counterbore including a disc and a, snap ring outward of said disc and engaged in a snap ring groove in said counterbore, and a compression spring interposed between said closure and said plunger biasing said plunger toward said shoulder, said plunger being coaxial- 1y recessed to receive one end of said spring and the disc of said closure means being provided with an inwardly projecting spring centering boss about which the other end of said spring is disposed.

HERBERT M. EMGE.

6 REFERENCES CITED The following references are o f. record in the file of this patent:

UNITED STATES PATNTS Number 

